Effect of Graphite Aging on Its Wetting Properties and Surface Blocking by Gaseous Nanodomains

0576103 - ÚFCH JH 2024 RIV US eng J - Článek v odborném periodiku
Tarábková, Hana - Janda, Pavel
Effect of Graphite Aging on Its Wetting Properties and Surface Blocking by Gaseous Nanodomains.
Langmuir. Roč. 39, č. 39 (2023), s. 14154-14161. ISSN 0743-7463
Institucionální podpora: RVO:61388955
Klíčová slova: Hydrophobicity * Carbon * Nanobubbles
Obor OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
Impakt faktor: 3.9, rok: 2022
Způsob publikování: Open access

Early works considered basal planes of highly ordered pyrolytic graphite (HOPG) as hydrophobic, relatively inert materials with low electrocatalytic activity due to nonpolar sp2 carbon. On the contrary, a freshly prepared HOPG surface exhibits intrinsically mildly hydrophilic properties, with a low contact angle of water, which increases after exposure to an ambient atmosphere. This process, called aging, ascribed to adsorption of airborne hydrocarbons, is reportedly accompanied by strong decay of electron transfer kinetics, the mechanism of which is not yet fully understood. Examining both freshly prepared and aged basal plane HOPG immersed in water by PeakForce quantitative nanomechanical imaging, we have found that aged HOPG is occupied by ambient gaseous nanodomains, the existence of which is explained by incomplete wetting. They cover up to 60% of the immersed surface and their incidence is in direct relation with graphite aging time. In contrast with aged graphite, gaseous nanodomains were absent on the freshly stripped HOPG surface. It can be concluded that ambient gaseous nanodomains can prevent aged basal plane HOPG from contact with aqueous media and may thus affect processes at the solid–liquid interface.
Trvalý link: https://hdl.handle.net/11104/0345710